=begin
In (({value_to_generic()})), ((|signed_p|)) seems to be ignored except for
(({TYPE_LONG})), and (({NUM2LONG()})) is used even if ((|signed_p|)) is not set.
(({NUM2INT()})) and (({NUM2UINT()})) have different value ranges, so I
think they should be separated.

And in (({generic_to_value()})), ((|signed_p|)) is ignored only for
(({TYPE_LONG_LONG})), and I can't see any reason to make the
difference.